[clang] [llvm] [CHERIoT] Define a RISCV target feature for XCheriot. (PR #189968)

[Owen Anderson via cfe-commits]

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@@ -1750,6 +1750,13 @@ def HasXAIFET : Predicate<"Subtarget->hasXAIFET()">,
                           AssemblerPredicate<(all_of FeatureVendorXAIFET),
                           "'XAIFET' (AI Foundry ET Extension)">;
 
+def FeatureVendorXCheriot
+    : RISCVExtension<1, 0, "CHERIoT extension",
+    [FeatureStdExtC, FeatureStdExtE, FeatureStdExtM]>;
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resistor wrote:

I could alternatively omit the dependency list entirely for now, since what I really need is the name to be recognized.

https://github.com/llvm/llvm-project/pull/189968